[bug] email client unable to handle "Content-Transfer-Encoding: base64"

asked 2018-10-09 18:22:40 +0300

arle
181 ●6 ●8 ●14

Email client doesn't show attachment nor download button available, just blank view. Below censored email sample

Return-path: <xxx@xxx.xx>
Envelope-to: xxx.xxxx@xxx.xx
Delivery-date: Mon, 08 Oct 2018 xx:xx:xx +0300
Received: from xxx.xxx.xx ([xxx.xx.xxx.xxx] helo=xxx.xxxx.xx)
        by xxxx.xxxx.xx with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)
        (Exim 4.89)
        (envelope-from <xxxx@xxx.xx>)
        id xxxxxxx
        for xxxx.xxxx@xxx.xxx; Mon, 08 Oct 2018 xx:xx:xx +0300
Received: from [xxx.x.x.x] ([xx.xx.xxx.xx])
        by xxxx.xxxx.xx  with ESMTP id xxxxx-xxxxxxxxxxx
        for <xxx.xxxx@xxxx.xx>; Mon, 8 Oct 2018 xx:xx:xx +0300
Content-Type: application/pdf
Content-Disposition: attachment; filename=xxxx_xxxxx.pdf
From: xxxx@xxxx.xx
To: xxx.xxxxx@xxxx.xx
X-Mailer: nodemailer (1.3.2; +http://www.nodemailer.com;
 SMTP/1.0.3[client:1.3.1])
Content-Transfer-Encoding: base64
Date: Mon, 08 Oct 2018 xx:xx:xx +0000
Message-Id: <xxxxxx-xxxxx-xxxx-xxxxxx@xxxx.xx>
MIME-Version: 1.0
X-SA-Exim-Connect-IP: xxx.xx.xxx.xxx
X-SA-Exim-Mail-From: xxxx@xxx.xx
X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on mail
X-Spam-Level: 
X-Spam-Status: No, score=-1.5 required=5.0 tests=BAYES_50,RCVD_IN_DNSWL_MED,
        SPF_PASS,TVD_SPACE_RATIO autolearn=no autolearn_force=no version=3.4.1
Subject: xxxxxxxxxx xxxxxx
X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000)
X-SA-Exim-Scanned: Yes (on xxxx.xxxx.xx)

#### Here starts 51537 characters long  base64 encoded pdf attachment ####